<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
</head>
<body>
    <script>
    function Person(name,age){
        this.name=name;
        this.age=age;
    }
    var quan=new Person("quan",18);
    console.log(quan._proto_==Person.prototype);
    console.log(Person.prototype);
    console.log(quan.toString());
    </script>
</body>
</html>